1. Field of the Invention
The present invention relates to monolithic ceramic electronic components and particularly relates to a monolithic ceramic electronic component including inner electrodes containing Ni and outer electrodes which are electrically connected to the inner electrodes and which are formed by plating.
2. Description of the Related Art
Outer electrodes of a monolithic ceramic capacitor, which is an example of a monolithic ceramic electronic component, are usually formed in such a way that a conductive paste is applied to end portions of a component body and is then baked. However, the thickness of the outer electrodes, which are formed in the above way, is large, about tens to hundreds of micrometers. Therefore, in order to adjust the size of the monolithic ceramic capacitor to a certain standard size, the effective volume for ensuring the electrostatic capacity needs to be undesirably reduced because the volume of the outer electrodes needs to be ensured.
In order to solve this problem, it has been proposed and has been in practical use that metal coatings are deposited directly on a component body so as to connect lead ends of inner electrodes to each other and each of the metal coatings is used as at least one portion of a corresponding one of the outer electrodes. For example, Japanese Unexamined Patent Application Publication No. 63-169014 discloses a method for forming outer electrodes in such a way that conductive metal layers are deposited by electroless Ni plating over side surfaces of a component body that have exposed inner electrodes such that the inner electrodes exposed on the side surfaces are shorted. According to the outer electrode-forming method, the volume of the outer electrodes can be reduced and therefore the effective volume for ensuring the electrostatic capacity can be increased.
However, a metal coating formed directly on a certain surface of a body of a component has a problem that the anchoring force between the metal coating and the component body is low because there is no glass or the like therebetween, unlike the electrodes formed by baking the conductive paste as described above. When the anchoring force therebetween is low, the interface between the metal coating and the component body may possibly be cracked and suffer from the ingress of moisture. Furthermore, the ingress of moisture into interfaces between ceramic layers and inner electrodes may possibly cause electrical shorts between the inner electrodes, which have different potentials, which impairs functions of the component.